Appearing on the breakfast show, Sammy Wilson said the draft withdrawal agreement, which will be put to the cabinet today, breaks Theresa May's repeated promise that "Brexit means Brexit".

"The promise that the Prime Minister made, that Brexit means Brexit, that we would leave the EU, that we would have a clean break with the institutions of the EU has not been fulfilled if what the headline of what we know in this deal is correct," he told Julia Hartley-Brewer.

"The UK is going to be kept inside the customs union, and will be kept inside the customs union, until the EU is satisfied."

Mr Wilson added that what he had seen of the deal suggested that Northern Ireland was kept "even more deeply" in the EU without "any exit mechanism".

'Door has been locked'

Sammy Wilson speaks at a 'Leave Means Rally'. Image: Getty

"The door has been locked and the key has been given to the EU, and they'll let us out when they're satisfied that we can't get out," he said.

The politician claimed that Ms May had "rolled over to EU negotiators" and demanded an "explanation".

"We're more than happy to sit down and talk to her [Theresa May] and get an explanation as to why the promises she has made not once, but hundreds of time, why she feels she can no longer honour them," Mr Wilson said.